Madison - The leading two Democrats in the recall race against Gov. Scott Walker broke sharply with one another Wednesday on how to restore collective bargaining rights for public workers in the state.

Milwaukee Mayor Tom Barrett made his sharpest criticism yet of a pledge by his opponent, former Dane County Executive Kathleen Falk, to veto any state budget that doesn't restore the union bargaining that was largely repealed for public workers by the Republican governor. Barrett pointed out that under Wisconsin's system vetoing a new budget bill would leave the budget signed by Walker and its cuts to education and local governments in place indefinitely.

"If we want to have a permanent Scott Walker budget, that's what we would be doing," Barrett said. "We can't play into (Republicans') hands."

Falk, who's won backing from the state's largest unions, said that the threat of a budget veto would be more effective than Barrett's plan of calling a special session of the Legislature to restore union bargaining.

"The only bill that has to pass the Legislature is the budget bill," Falk said. "It's really important that we have the budget bill restore collective bargaining, and it's really important to have a governor who has the courage to do it."

Barrett, Falk, Sen. Kathleen Vinehout (D-Alma) and Secretary of State Doug La Follette - the four Democrats seeking to run against Walker - preached the gospel of recall to a standing room-only crowd of hundreds in a downtown hotel in the capital city. There's less than a month left until the May 8 primary, and the candidates are running a spirited race to be part of the third recall election for a governor in U.S. history on June 5.

Republicans countered that the recall effort and the Democratic candidates would move the state in the wrong direction.

"Now that we've laid the foundation for economic growth, this election is a choice between moving Wisconsin forward under Governor Walker, or moving backward to the failed liberal policies that resulted in rampant job loss and deficit spending," said Ben Sparks, spokesman for the state Republican Party.

In the debate over collective bargaining, Vinehout and La Follette both said that a new governor could take steps to restore better labor relations right away by ordering his or her administration to start meeting and talking with labor leaders again to get their input and respond to their concerns.

Also Wednesday, Barrett released his first campaign ad and snagged the endorsement of U.S. Sen. Herb Kohl, a popular retiring Democrat who resisted pressure by some in his party to run against Walker in the recall.

"While I wouldn't ordinarily endorse in a primary, this is no ordinary race or time. Tom's decision to run speaks volumes about who Tom is - a strong leader known around the state as someone who will work with everyone to help bring Wisconsinites together and move our state forward again," Kohl said in a statement.

Kohl has not endorsed a candidate in a Democratic primary before with the exception of his nephew Dan Kohl, who ran unsuccessfully for the state Assembly in 2008.

Barrett's simple ad comes a week and a half after his entry to the race and features the Democrat speaking into the camera and talking about why Walker should be removed from office. It's running in an undisclosed number of markets in the state.

"Scott Walker has divided our state, and while he's pursued his ideological agenda, last year Wisconsin lost more jobs than any state in the country," Barrett said in the ad.

Walker spokeswoman Ciara Matthews countered that Barrett had lost to Walker in the 2010 governor's race because of his policies as mayor.

"Barrett is attempting to focus on anything except his failed record of raising taxes, increasing government spending and devastating job loss in his city," Matthews said.

Barrett and Falk have already established themselves as front-runners in polls and endorsements. Falk has won endorsements from major public-sector unions, including the Wisconsin Education Association Council and the American Federation of State, County, and Municipal Employees, and the Wisconsin State AFL-CIO. Falk has also been endorsed by several lawmakers and by environmental and women's groups.

Barrett has also been endorsed by U.S. Rep. Ron Kind (D-La Crosse) as well as several Democratic lawmakers, including Sens. Jon Erpenbach (D-Middleton) and Tim Cullen (D-Janesville).

About Jason Stein

Jason Stein covers the state Capitol and is the author with his colleague Patrick Marley of "More than They Bargained For: Scott Walker, Unions and the Fight for Wisconsin." His work has been recognized by journalism groups such as the American Society of News Editors, the Society of American Business Editors and Writers, and the Association of Capitol Reporters and Editors.